1. Technical Field
Various embodiments of the present disclosure relate to converters and methods of fabricating the same and, more particularly, to switched-capacitor Direct Current-to-Direct Current (DC-to-DC) converters and methods of fabricating the same.
2. Related Art
Switched power converters used in power supplies may be typically categorized as either switched-inductor converters (SICs) or switched-capacitor converters (SCCs). The SICs may store energy in their inductors while the SICs convert a source of direct current (DC) from one voltage level into another voltage level, and the SCCs may store energy in their capacitors while the SCCs convert a source of direct current (DC) from one voltage level into another voltage level. The SICs may exhibit a wide operating range and a high efficiency. Thus, the SICs have been widely used in application fields of high power. However, there may be some limitations in employing the SICs in compact systems because inductors of the SICs occupy a relatively large area. In contrast, the SCCs may be suitable for low power systems having a compact size because capacitors of the SICs occupy a relatively small area as compared with the inductors of the SICs. Recently, the SCCs have been widely used in mobile systems because of their compact size and low electromagnetic interference.
In general, in the event that switching elements and capacitors are integrated in a single chip, there may be a limitation in increasing a capacitance value of the capacitors because of a planar area that the capacitors occupy. Moreover, since a high temperature process is used in fabrication of the capacitors, characteristics of transistors constituting the switching elements may be degraded due to the high temperature process. Thus, the capacitors have been separately fabricated from the chip including the switching elements such as the transistors and have been disposed outside the chip.